A refrigerator is utilized to store various foodstuffs under either a frozen or a refrigerated condition for extending the freshness of the foodstuffs stored in the compartment. Such a refrigerator consists of either one of two cooling types, one being a direct cooling type, that is, an evaporator in the refrigerating cycle is installed in a foodstuff storage chamber, and a direct heat-exchange is obtained. The other type of cooling is the indirect cooling type, that is, an evaporator is mounted in a passage, which is separated from the foodstuff chamber, and air which is heat-exchanged by the evaporator is directed to the foodstuff storage chamber by means of a fan.
The refrigerator normally consists of freezing and refrigerating compartments, one being located above the other. Furthermore, the refrigerating compartment is provided with a separate chamber, having a different temperature from that of the refrigerating compartment, known as a "vegetable compartment" or a "chilled compartment" which stores meats etc. The foodstuffs can be separately stored in the chamber in accordance with the desired conditions. On the front surface of each of the freezing and refrigerating compartments a door is installed. The doors hinge on one vertical side in order to provide access to the foodstuffs in their respective compartment. For the passage of cool air, a condenser and a fan are installed in the rear wall of the freezing compartment.
The refrigerator gains advantages that result from the increase in the storage volume and the convenience of the door operation. However, problems may occur when various types of fermented foodstuffs, e.g. kimchi, are stored together with other foodstuffs in the same chamber.
Since kimchi is usually made in a voluminous and heavy amount, a large storage chamber is required. Food stored alongside the kimchi container are affected by the kimchi. Particularly, when kimchi is being fermented, it produces a unique odor which remains in the cool air and circulates in the compartment. There is a problem in that the odor often adversely affects other foodstuffs.
To resolve the above defect, a refrigerator having a separate compartment is disclosed in U.S. patent application Ser. No. No. 08/115,046 (1993.). The refrigerator, as shown in FIG. 5, has a freezer compartment 1, a refrigerating compartment 2 located beneath the freezer compartment 1, a kimchi chamber 3 located beneath the refrigerating compartment 2, and a vegetable compartment 4 located beneath the kimchi chamber 3. The kimchi chamber 3 contains its own cooling and heating mechanisms 31,32 which are mounted on the external surfaces of the walls which form the kimchi chamber 3. The kimchi chamber 3 can be used to ferment and then store food such as kimchi.
Since the conventional refrigerator has an isolated kimchi chamber as described above, and separation of compartments, the air of the kimchi chamber can not smoothly circulate. Thus, the air of the kimchi chamber stays in the kimchi chamber for a long time. This makes foodstuffs stored in the kimchi chamber unsanitary and can cause the user some displeasure.
In particular, the air of the closed kimchi chamber is heated to a higher temperature by heat used to ferment the kimchi. Thus, to solve the ventilation problem the kimchi chamber has to employ cool air inflow and discharging openings to promote the circulation of air through the kimchi chamber. In this case, other problems occur due to the transfer of relatively higher temperature air from the kimchi chamber to another other compartment which has a lower temperature. That is, when the kimchi is fermented the temperature of the air of the kimchi chamber rises 30 degrees. In case that the relatively warmer air is introduced to the evaporator directly, and is combined with the relatively lower cool air from the other compartment at the entrance of the evaporator, the evaporator is easily covered over with frost and this causes the cooling efficiency of the evaporator to decrease. Further, if the air from the kimchi chamber flows into another compartment e.g. the vegetable compartment, the vegetables stored in the vegetable compartment can not retain their freshness for a long period of time.